Quote from: Serge on July 18, 2012, 07:44:15 PM

Quote from: floeti on July 18, 2012, 07:24:31 PM

Quote from: aq on July 18, 2012, 02:53:01 PM

Quote from: floeti on July 18, 2012, 02:38:24 PM

Nevertheless, I think this problem can be solved by using something like smartcards, which store the private keys and are able to sign transactions (with prior decryption through a passphrase). So the private keys never leave the smart card. Combine this with some kind of dedicated smart card interface-device, that displays the to-be-signed transaction and one should be reasonably safe. This concept is not new at all, but unfortunately not availiable for bitcoin, yet. Expect huge price jumps, if it is announced! Grin

http://bitcoincard.org/
forum threads about it:
https://bitcointalk.org/index.php?topic=78171.0
https://bitcointalk.org/index.php?topic=85832.0
https://bitcointalk.org/index.php?topic=88645.0

I know about this, but it's not quite what I meant. As far as I can see, there is no possibility to password protect the keys, nor is there a possibility to make a physical backup of the keys. So if the hardware breaks, your coins are lost. So it's not secure enough to store many coins over a longer term. Nevertheless Bitcoincard will be great for everyday use.

you can store the keys on paper in safe or safe deposit box, you can also make a brain wallet with a passphrase that only you know and not have private keys anywhere else until you have to restore them to access coins from your brainwallet

As far as I understood the Bitcoincard generates the private keys and they can never leave the device. So a paper wallet or brainwallet would not work.